Pmbus Command Details; Addressing And Write Protect - Analog Devices LTM4683 Manual

PMBus COMMAND DETAILS

ADDRESSING AND WRITE PROTECT

CMD
COMMAND NAME CODE DESCRIPTION
PAGE 0x00 Provides integration with multi-page PMBus devices.
PAGE_PLUS_WRITE 0x05 Write a supported command directly to a PWM channel. W Block
PAGE_PLUS_READ 0x06 Read a supported command directly from a
WRITE_PROTECT 0x10 Level of protection provided by the device against
MFR_ADDRESS 0xE6 Sets the 7-bit I
MFR_RAIL_ADDRESS 0xFA Common address for PolyPhase outputs to adjust
PAGE
The PAGE command provides the ability to configure, control and monitor both PWM channels through only one physi-
cal address, either the MFR_ADDRESS or GLOBAL device address. Each PAGE contains the operating commands for
one PWM channel.
Pages 0x00 and 0x01 correspond to Channel 0 and Channel 1, respectively, in this device.
ASEL_01 sets the address for Channel 0 and Channel 1, and ASEL_23 sets the address for Channel 2 and Channel 3.
Each of the ASEL pins will have a different programmed address.
Setting PAGE to 0xFF applies any following paged commands to both outputs. With PAGE set to 0xFF , the LTM4683
will respond to read commands as if PAGE were set to 0x00 (Channel 0 results).
This command has one data byte.
PAGE_PLUS_WRITE
The PAGE_PLUS_WRITE command provides a way to set the page within a device, send a command, and then send
the data for the command, all in one communication packet. Commands allowed by the present write protection level
may be sent with PAGE_PLUS_WRITE.
The value stored in the PAGE command is not affected by PAGE_PLUS_WRITE. If PAGE_PLUS_WRITE is used to send
a non-paged command, the Page Number byte is ignored.
This command uses the Write Block protocol. An example of the PAGE_PLUS_WRITE command with PEC sending a
command with two data bytes is shown in Figure 53.
1
SUBORDINATE
S
ADDRESS
PAGE_PLUS_READ
The PAGE_PLUS_READ command provides the ability to set the page within a device, send a command, and then read
the data returned by the command, all in one communication packet.
PWM channel.
accidental changes.
2
C address byte.
common parameters.
7 1 1 8
PAGE_PLUS
W A A
COMMAND CODE
8 1
LOWER DATA UPPER DATA
A
BYTE
Figure 53. Example of PAGE_PLUS_WRITE
For more information
TYPE
R/W Byte
Block
R/W
R/W Byte
R/W Byte
R/W Byte
1 8 1 8
BLOCK COUNT PAGE
A
(= 4) NUMBER
8 1 8
A
PEC BYTE
BYTE
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LTM4683
DATA
PAGED FORMAT UNITS NVM
N Reg
N
N
N Reg
N Reg
Y Reg
1 8 1
COMMAND
A A ...
CODE
1 1
A P
4683 F53
DEFAULT
VALUE
0x00
Y 0x00
Y 0x4F
Y 0x80
Rev. 0
83